Change in China’s Sex Ratio at Birth Since 2000: A Decomposition at the Provincial Level

Abstract

China’s sex ratio at birth (SRB) has drawn much attention, but contributions of individual provinces to the high national SRB have been neglected in the literature despite marked regional differences across the country. Using data from China’s censuses and inter-census surveys since 2000, we devised a decomposition method and examined the changes in provincial composition of births (PCB), parity composition by province (PCP), and male proportion by parity (MPP) and their contributions to the change in national SRB. We found that the national SRB change was most heavily influenced by the change in PCP and MPP, whereas at the provincial level the magnitude of PCB contribution was much larger than those of PCP and MPP. Due to the marked difference in SRB by parity, the decline in the proportion of first births and an increase in the proportion of higher-order births increased the national SRB. The consistent decline in the proportion of males in second and above parity births lowered national SRB, while the male proportion of first-parity births increased national SRB. Different provinces contributed to the change in national SRB at different levels of magnitude, and the above three factors exhibited regional differences.